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     See ◄Introduction to switches►
 
     This switch is especially useful if the format of your files is
     incompatible with this version of COBOL.
 
     Setting this switch to on means that when a program writes records to
     a line sequential file with a record containing control characters
     (that is, all characters with ASCII codes less than or equal to
     x"1B"), the system adds a null character (x"00") before each
     control character. Similarly, on reading a record from a line
     sequential file, these null characters are stripped from the control
     characters.
 
     Setting this switch affects only the physical storage of data in a
     line sequential file. Records written with one setting and read back
     with the same setting are returned in exactly the same way. However,
     you should note that if you attempt to input a file with one setting
     that had been output with the other setting, the results are
     unpredictable.
 
     Setting this switch off allows control characters to be written and
     read in the same way as other characters.
 
     When the N switch is on:
 
      o  Any character is allowed in the data record of a line
         sequential file.
 
      o  Each record is examined before it is written. All characters
         whose value is less than x"1B" are written with a preceding null
         (x"00") to form 2-byte pairs. On output to disk, trailing spaces
         are removed, and a record terminator of x"0D0A" is appended to
         terminate the record.
 
      o  The file is read as records, some of which may contain 2-byte
         pairs where the first byte is null. The records are terminated
         by a record terminator. The leading null of each 2-byte pair is
         removed to give the final data record. Tabs (x"09") that do not
         form part of a 2-byte pair are expanded.
 
     Note:
 
      Control characters depend on the operating system. Their hexadecimal
      values are always less than x"1B". CR (x"0D"), LF (x"0A"),
      TAB (x"09"), NUL (x"00"), and EOF (x"1A") are all recognized control
      characters on DOS and OS/2.
 
 
     When the N switch is off:
 
      o  Data records in a line sequential file must contain only ASCII
         text characters (those with a value greater than x"1B").
 
      o  Trailing spaces are removed on output to disk, and a record
         terminator of x"0D0A" is appended to terminate the record.
         Printer control characters may also be written to disk.
 
      o  The file is read as data records with each record terminated by
         a record terminator. If the data contains either x"0D" or x"0A",
         results can be unpredictable. Tab characters (x"09") are
         expanded to spaces; otherwise the data record is returned intact.
 
 
     For example, the command:
 
       A:MYPROG (-N)
 
     loads the program MYPROG from drive A. It also specifies that in line
     sequential files, all characters less than x"1B" except for TAB
     and the file control characters are treated as data. Null is not
     inserted before data characters less than x"1B" on output.
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